NHLBI Study Suggests Symptom-Driven
Therapy May Be Sufficient For Some Adults With Mild
Persistent Asthma

Some adults with mild persistent asthma may be able
to adequately control their asthma by taking corticosteroids
only when needed, instead of taking anti-inflammatory
medication daily, according to new results from the
Improving Asthma Control Trial (IMPACT). Conducted by
the National Heart, Lung, and Blood Institute’s (NHLBI)
Asthma Clinical Research Network, the one-year, multi-center
study found that participants who were treated with
corticosteroids intermittently based on symptoms had
about the same rate of severe exacerbations and of asthma-related
lung function decline as those treated with the standard
recommendation of daily long-term control medication.

Asthma is considered mild and persistent when individuals
have acute symptoms such as wheezing, coughing, or chest
tightness more than twice a week, but not daily, or
they have night-time awakenings due to asthma more than
two nights a month. The researchers caution that the
new findings might not apply to people who have recently
developed asthma. In addition, they do not apply to
patients with more frequent symptoms or more severe
asthma. The results are published in the April 14 issue
of the New England Journal of Medicine.

“This study provides evidence of another possible way
to treat adults with long-standing mild persistent asthma,” stated
Elizabeth G. Nabel, MD, director of the NHLBI, part
of the National Institutes of Health. “If additional
research confirms these findings, then some of these
patients may be able to safely treat their asthma with
intermittent medication and avoid the added expense
and inconvenience of daily therapy. As for all asthma
patients, however, individuals should work closely with
their healthcare providers to develop and follow the
treatment plan that suits them best.”

More than 20 million Americans have asthma. For those
with mild persistent asthma, guidelines from the National
Asthma Education and Prevention Program (NAEPP) currently
recommend daily long-term control medication to prevent
symptoms and quick-relief medication (inhaled bronchodilator)
to treat acute asthma symptoms if they occur.

The recommendation for daily long-term control medication
for mild persistent asthma was based largely on clinical
trials that showed that anti-inflammatory therapy improves
lung function and measures of asthma control. However,
participants in these earlier studies had asthma that
ranged in severity from mild to moderate, according
to the IMPACT authors. The IMPACT study strictly adhered
to the guidelines’ definition.

James Kiley, PhD, director of the NHLBI Division of
Lung Diseases, commented, “By focusing exclusively on
mild persistent asthma, the IMPACT study has added to
our understanding of possible treatment options for
different levels of asthma severity.”

NAEPP is expected to release updated guidelines in
2006. An expert panel will consider the results of IMPACT
and other studies to determine if changes in treatment
recommendations for adults with mild persistent asthma
are warranted.

IMPACT was designed to identify the best long-term
treatment strategy for adults with mild persistent asthma.
Researchers compared changes in lung function, frequency
and severity of asthma symptoms, and quality-of-life
scores in 255 adult patients. Participants were randomly
selected to one of three treatment groups. Two groups
were assigned to long-term control medication taken
twice daily — either an inhaled steroid (budesonide)
or a leukotriene modifier (zafirlukast) taken in pill
form. The third group received placebo (inactive) medication.
All participants were given medications for asthma symptoms — inhaled
bronchodilator (albuterol), inhaled corticosteroid (budesonide),
and oral corticosteroid (prednisone) — with explicit
instructions on when and how to use these treatments
depending on the severity and duration of the individual’s
symptoms.

After one year, changes in lung function and the number
of severe attacks did not significantly differ among
the three groups. In addition, participants scored similarly
on quality-of-life tests regardless of treatment group.
Those in the daily inhaled steroid group, however, reported
significantly more symptom-free days (equivalent to
about 26 additional symptom-free days per year) than
participants in the other two treatment groups.

“Although some reports of symptoms differed between
those taking budesonide daily and the other participants,
these differences were not reflected in the quality-of-life
scores,” noted Homer Boushey, M.D., Principal Investigator
at the University of California San Francisco, and a
lead author of the study. “Combined with the fact that
there were no significant differences in lung function
changes or in the frequency of severe attacks among
the treatment groups after a year of treatment, we conclude
that, overall, the three treatments had similar clinical
effects in this study of mild asthma.”

Other reports have noted that many asthma patients
do not follow recommendations for daily controller medication. “The
results of IMPACT suggest that for some adults with
long- standing mild persistent asthma, choosing not
to take daily medications might be okay,” added Elliot
Israel, M.D., Principal Investigator at Brigham and
Women's Hospital in Boston and the co-lead author. “But
this choice should be made in consultation with the
patient’s healthcare provider. It’s critical that individuals
with more severe asthma follow recommendations for daily
long-term control medications and that all asthma patients — even
those with mild asthma — be aware of signs of
worsening asthma and adequately treat their symptoms.”

Asthma treatment guidelines also recommend written
action plans as part of an overall effort to educate
patients in self-management. The plans provide guidance
for patients on how to monitor and treat their asthma,
including how to recognize when their condition worsens.
In general, action plans are based on the patient’s
symptoms or on “peak flow” measurements of lung function,
which can be taken by patients using a hand-held device.

“One of the most important things we did during this
study was to work closely with the participants to help
them effectively manage their asthma,” noted Boushey. “Patients
need to know how to recognize asthma symptoms, what
to do when symptoms begin, and — perhaps most
essential — they must have at hand the means to
treat their symptoms quickly.”

The data coordinating center is at Penn State College
of Medicine, Penn State Milton S. Hershey Medical Center,
Hershey, PA.

The medications for IMPACT were donated by Astra-Zeneca
Pharmaceuticals, headquartered in Wayne, Pennsylvania.

To interview an NHLBI expert, please contact the NHLBI
Communications Office at 301-496-4236. To interview
Dr. Boushey, please contact Wallace Ravven, at the University
of California, San Francisco Department of Public Affairs
at 415-476-2557. To interview Dr. Israel, please contact
Melanie Franco at the Brigham and Women’s Hospital Department
of Public Affairs at 617-534-1600.

NHLBI is part of the National Institutes of Health
(NIH), the Federal Government's primary agency for
biomedical and behavioral research. NIH is a component
of the U.S. Department of Health and Human Services.
Additional information about asthma and other NHLBI-supported
research and educational programs are available online
at the NHLBI website, www.nhlbi.nih.gov.